Pneumatic conveyer tube



Filed Jan. 5, 1955 2 Sheets-Sheet l a/zzzzm Ji$25$221 &&

A TORNEY Patented Oct. 8, 1935 UNITED STATES PATENT OFFICE 7 Claims.

Among the principal objects which the present invention has in view are: To increase the sensitiveness of the control valves; and to simplify the construction and arrangement of the parts of said valves.

Figure 1 is a fragmentary view of a conveyer tube showing a receiving and delivery station and air drainage tube and control valve therefor;

Figure 2 is a top plan view on enlarged scale of a control valve and housing therefor, said valve being constructed and arranged in accordance with the present invention;

Figure 3 is a cross section of the valve and valve casing, the section being taken as on the line 3-3 in Figure 2, the valve member being shown in normally closed position;

Figure 4 is a similar view, the valve member being shown in fully opened position.

As is well understood, pneumatic systems of the character herein disclosed have employed valve members for cutting off the vacuum source when the air pressure in the delivery tube has approached the normal, to thus avoid the bleeding of the vacuum supply.

As seen in the drawings, especially in Figure 1 thereof, the tube 9 has a receiving bell-mouth I normally open to receive the carrier employed in this character of systems. At the delivery end of this tube is a valve or gate which is opened by or at the approach of said carrier for the delivery thereof to a station where the clerk or operative may receive the carrier. Usually at the same station there is a receptacle device for receiving the carrier when being sent to or delivered to the cashiers desk. When, on this flight, the carrier reaches the gate, the same is forced open thereby and the carrier is emitted from the tube, the gate immediately closing then. The carrier has been thus moved through the tube by the mechanism providing an air exhaust system with which said tubes are connected to a pipe I2 and a valve casing I3.

The valve casing I3 is constructed to open when the tubes 9 are closed as by the introduction therein of the carriers abovementioned. Normally, there is a flow of air through the tubes 9 in correspondence with the opening of the valve in the casing I2. The working condition is, in this manner, established so that an unbalanced condition may arise in any tube where the carrier has been introduced to interrupt the flow of air referred to. Immediately thereafter, the flapper is opened to its fullest extent as shown in Figure 4 of the drawings. From this it will be seen that the pull of the exhaust system on the carrier tube 9, thus closed by the carrier, empties the same, of air, in advance of the carrier, permitting the air pressure there behind to thrust the carrier to its destination. When the carrier reaches its destination, it is expelled from the tube and the tube being freely supplied thereafter with atmospheric air, the flapper is drawn quickly into the closed position, shown in Figure 3 of the drawings.

It is obvious that the flapper I4 should be very sensitive to the balance of pressure. To this 'e'nd,the flapper I 4, in the instant disclosure, is normally suspended upon a pull spring I5. A normal position of the flapper is the result of the pressure exerted by the atmospheric pres-. sure in the tube 9 when open as against the rarifled atmosphere in the pipe I2 below the said flapper; The regulation to meet this position of the parts is accomplished by means of the elongated set screw which is mounted in an extension I! of the casing I3. A cut I8 is provided at the free end of the spring I5, while the opposit'e end of the spring is anchored to the stud I9'on the flapper construction.

It will be obvious from the foregoing that by operating the screw I 6, the tension on the spring l may be regulated to suspend the flapper as desired.

In the present case, and as shown best in Figure 3 'of the drawings, it is desired that the flapper be lifted or supported so that a slight opening at the outer end of the flapper shall be maintained within the casing I3. This opening is provided so that a suflicient exhaustion of the air in the tube 9 may be drawn through the seat under the flapper I 4 at all times to maintain what may be termed the alert position of the carrier system.

In the present construction, the flapper is rigidly mounted in the casing I3, being held in position by the screws 20. The flapper is constructed primarily of the metal plate 2|, and has mounted thereon, a deadener 22, such as a layer of leather, asbestos, or other suitable material.

A tension spring 23 is mounted upon the flapper I I preferably under the screws securing the same. The tension spring is bowed, as seen best in Figures 3 and 4 of the drawings, to bear slidingl'y upon the free end of the flapper III. This pressure counteracts any tendency to chatter or rumble which may be imparted to the flapper, and by it, throughout the system, due to any vibration as caused between the slight variant of the air pressure and vacuum pressure.

In some instances, I have provided a set screw 24 which is mounted in the casing I3 and in tapped perforation through the side wall thereof, the screw 24 being arranged to bear upon or support the flapper in its'fully seated position. By means of this screw, the opening at the free end of the flapper can be increased or diminished at will.

A similar purpose is served by the screw 25 which is disposed to rest in the path of, and contact with, the tension spring 23 when the flapper I4 is raised to the open position as shown in Figure 4 of the drawings.

It is obvious that with a valve constructed as herein disclosed, the action is very sensitive. The pull of the spring 15 at the free end of the flapper I4, constructed to curl or bend upward, is very effective and is quickly responsive to the variation in the two pressures upon the valve I4, above referred to. Also, it will be noted that in opening, the curling action of the flapper gradually and proportionately opens as the atmospheric pressures vary. Also, it will be noted that when this valve closes, it does so with a gradual movement and effect which overcomes any tendency to' hammer or otherwise jar the system.

I claim:

1. A conveyer embodying an open-ended delivery tube, an air exhaust system operatively connected with said tube, and a valve for controlling the flow of air from said tube to said exhaust system, said valve being adapted to curl to open progressively, and means for so opening said valve in correspondence with the balance of air pressure on said valve.

2. A conveyer embodying an open-ended delivery tube, an air exhaust system operatively connected with said tube, and a valve for controlling the flow of air from said tube to said exhaust system, said valve being adapted to bend progressively, and means for bending said valve in correspondence with the pressure of air on said valve, said means embodying a rigid mounting for said valve and a suspension spring operatively connected with said valve at approximately the edge thereof in line with and removed from said mounting.

3. A conveyer embodying an open-ended delivery tube, an air exhaust system operatively connected with said tube, and a flexible valve for controlling the flow of air from said tube to said exhaust system, said valve being adapted to bend to open progressively from one edge thereof, and means for so bending said valve when and as the pressure of the air on said valve is lowered below the pressure of said exhaust system on said valve, said means embodying a suspension spring operatively connected with said valve at approximately the edge thereof, and means for rigidly mounting the said valve at a point in line with the point of attachment of said spring, and means incorporated in the body of said valve for rendering said valve resilient in line between said rigid mounting of said valve and the edge of said valve adjacent the attachment of said spring thereto.

4. A conveyer embodying an open-ended delivery tube, an air exhaust system operatively connected with said tube, and a flexible closure valve for controlling the flow of air from said tube to said exhaust system, said valve being adapted to open progressively, and means for so opening said valve when and as the pressure of the air on said valve is below the pressure of said exhaust system on said valve, said means embodying a suspension spring operatively connected with said valve at approximately the free 5 edge thereof, and means for rigidly mounting the said valve at a point in line with the point of attachment of said spring, and means incorporated in the body of said valve for rendering said valve resilient between said rigid mounting 10 of said valve and the edge of said valve adjacent the attachment of said spring thereto.

5. A conveyer embodying an open-ended delivery tube, an air exhaust system operatively connected with said tube, and a flexible valve for 15 controlling the flow of air from said tube to said exhaust system, said valve being adapted to open progressively, and means for so opening said valve when and as the pressure of the air on said valve is below the pressure of said exhaust system 20 on said valve, said means embodying a suspension spring operatively connected with said valve at approximately the free edge thereof, and means for rigidly mounting the said valve at a point in line with the point of attachment of said 25 spring, and means incorporated in the body of said valve for rendering said valve resilient between said rigid mounting of said valve and the edge of said valve adjacent the attachment of said spring thereto, said means embodying a 30 finger spring rigidly attached to the casing in which said valve is located, and having a sliding contact with the valve adjacent the point of attachment of said spring and said valve.

6. A conveyer embodying an open-ended de- .35 livery tube, an air exhaust system operatively connected with said tube, and a valve for controlling the flow of air from said tube to said exhaust system, said valve being adapted to open progressively, and means for so opening 40 said valve when and as the pressure of the air in said tube on said valve is lowered below the pressure of said exhaust system on said valve, said means embodying a suspension spring operatively connected with said valve at approxi- 5 mately the edge thereof, and means for rigidly mounting the said valve at a point in line with the point of attachment of said spring, and means incorporated in the body of said valve for rendering said valve resilient in line between 5 said rigid mounting of said valve and the edge of said valve adjacent the attachment of said spring thereto, said means embodying a spring finger rigidly attached to the casing in which said valve is located, to have a sliding contact with the valve adjacent the lifting edge of said valve, and means adapted to control the lift of said valve.

7. A conveyer embodying an open-ended delivery tube, an air exhaust system operatively 0 connected with said tube, and a valve for controlling the flow of air from said tube to said exhaust system, said valve being adapted to open progressively, and means for so opening said valve when and as the pressure of the air in said 5 tube on said valve is lowered below the pressure of said exhaust system on said valve, said means embodying a suspension spring operatively connected with said valve at approximately the edge thereof, and means for rigidly mounting the said valve at a point diametrically opposite the point of attachment of said spring, and means incorporated in the body of said valve for rendering said valve resilient in line between said rigid mounting of said valve and the edge of said valve adjacent the attachment of said spring thereto, said means embodying a finger spring rigidly attached to the casing in which said valve is located to have a sliding contact with the valve 5 adjacent the lifting edge of said valve, and

means adapted to control the lift of said valve, said means embodying a set screw threadmounted. in the casing for said valve and in the path thereof to limit the lift thereof.

WILLIAM H. DINSPEL. 

